Observations on Some Unusual Toxic Effects of Sulphanilamide Therapy

seems more likely that it is due to the formation of a pigment in the body from the condensation products of the drug itself (Marshall and Walzl, 1937). Posner and his colleagues (1938) described a highly unstable form of methsemoglobin which they thought, might account for cyanosis in some of these cases. In many instances, however, the cyanosis is associated with sulphor methaemoglobinaemia (both intracorpuscular). Sulphaemoglobinsemia is due to the union of the intestinal sulphuretted hydrogen with haemoglobin, a reaction which is catalysed by sulphanilamides. This untoward effect may be avoided by withholding purgatives, except very mild ones like liquid paraffin, by giving a low residue diet and excluding articles containing sulphur, eggs, onions, garlic, etc. [Archer and Discombe (1937), Paton and Eaton (1937)]. Methaemoglobin however causes no trouble as it is rapidly ?reconverted into haemoglobin when treatment with sulphanilamide drugs is stopped and glucose and oxygen administered. Nausea with epigastric pain and occasionally vomiting may be produced by this group of drugs. These symptoms are more common with the newer remedy, M. & B. 693. It usually stops after the drug is withdrawn. Drug fever may occur seven to twelve days after the treatment has been started but is not common. A rash occurs in about six per cent of cases [Hageman and Blake (1938)]. Hallam (1939)